Abstracts Book - IMRC 2018

• SB1-P043
PREPARATION AND CHARACTERIZATION OF EPOXY VITRIMERS
WITH METAL CATALYSTS
Rodrigo Cunha 1 , Marcio Nele 2 , Marcos Lopes Dias 1
1 Universidade Federal do Rio de Janeiro, Institute of Macromolecules Professor Eloisa Mano,
Brazil. 2 Universidade Federal do Rio de Janeiro, Chemical Engineering Program at COPPE,
Brazil.
Vitrimers are a new class of cross-linked materials that show characteristic of
processable materials with Arrhenius flow behavior, not requiring precise
temperature control. These materials, are thermally malleable polymers that
exhibit bond exchange reactions (BER) and can reorganize their network
topology without compromising material’s integrity. Among target raw
materials, diepoxides and polyacids have been widely studied as an option to
form epoxy based vitrimers, due to their technological relevance. However,
optimum combinations of flexible chain epoxy resin and fatty acids suitable for
an environmentally friendly process are not yet established in the literature. In
this context, the present work proposes a study on the formation of
polyhydroxyesters with diepoxy monomers such as diglycidyl polyethylene
glycol (DGPEG) and different di and tricarboxylic acids with different chain sizes
such as adipic acid (AD) and citric acid (CA). Syntheses were carried out with
metal catalyst and concentrations of 1 and 5 mol% to promote catalytic
transesterification reaction assisted by thermal curing. Two efficient catalysts in
transesterification reactions was used in this study: zinc acetate (Zn(OAc)2) and
stannous octoate (Sn(Oct)2). The effect of catalyst concentration on the
dynamics of the bond exchange reaction in the polymer network were also
analyzed. A study of the structure, morphology and thermomechanical
properties of the vitrimers was carried out. Synthesized materials were
characterized by Fourier Transform Infrared Spectroscopy (FTIR). Thermal and
thermal properties was investigated by differential scanning calorimetry (DSC)
and thermogravimetric analysis (TGA). Polymerization degree was determined
FTIR by the increase in the intensity of the ester band at 1737 cm-1 and decrease
of the epoxy band at 914 cm-1. The DSC analysis of monomers DGPEG
presented melting temperature (Tm) of -2 oC and thermally cured materials
synthesized with zinc acetate (Zn(OAc)2) and stannous octoate (Sn(Oct)2 at
140oC for 12 hours exhibit glass transition temperature at -31 oC and -29 oC,
respectively. These values are in a range suitable for the application.